<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>HELLO WORLD</title>
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<h1>大家好，我是标题1</h1>

<h2>大家好，我是标题2</h2>

<p>大家好，我是段落-HTML</p>
<script type="text/javascript">
	
	var a=5
	if (a>3){
		alert("大于3");
	}else if(a<3){
		alert("小于3");
	}else{
		alert("等于3");
	}
</script>>

</body>
</html>